The invention relates to a method and device for processing data of an automation system for a building system engineering installation. According to the invention, the data of the automation system and data of system nodes (14, 15) of the installation are interlinked and assigned to one another. To this end, the system nodes (14, 15) connected to the automation system are detected, said system nodes (14, 15) are interlinked by means of data that can be retrieved from data memories (1, 2, 3) and by using system rules for assigning the system nodes, and the system nodes (14, 15) that are assigned to one another communicate with one another via the automation system. The system nodes (14, 15) that are automatically detected beforehand are assigned and linked, in particular, by an installation device (12) which is connected to the automation system, contains all communications rules, address and linking data, and which automatically assigns the system nodes (14, 15).